Advertising space is scarce. No wonder advertisers are innovative when it comes to taking advantage of underutilized real estate--such as the human skin.

Handvertising USA is an Orange County-based company that connects advertisers with customers willing to display ads on their hands.

"Almost everyone has been to a county fair, swap meet, bar or club and had had their hand stamped for proof of entry. We have found a better use for this space that could make everyone happy," says CEO Mike Brown. "We find venues also use the stamps to increase business. For example, venues are offering special prices on drinks if the customer has a particular Handvertising stamp. People are requesting particular stamps because they want to fit in and they want the drink special," he says.

Both examples indicate the renaissance of the human body in the marketing mix. While sidewalk wavers and door-to-door promoters are part of the old-school marketing arsenal, the new solutions are more sophisticated and go literally under the skin. Not only are the borders between human body and technology slowly disappearing; advertising, network, commerce, and consumer are converging as well.

Humans are still the best hardware. (By the way, they're still the most powerful software, too; it will take at least five more years, experts forecast, to develop a computer processor that is on par with the capabilities of a 6-year old child.) Consequently, NTT DoCoMo, Japan's largest wireless operator, is working on a mobile phone that sends electric signals through the human body to transmit data, enabling electronic payments or data transfer at the touch of a finger.